BY GORAN FALKENBERG
Department of Medical Physics, Karolinska Institutet, S-104 01 Stockholm, Sweden(Received 9 March 1972)
Department of Medical Physics, Karolinska Institutet, S-104 01 Stockholm, Sweden(Received 9 March 1972)
Bufotenine, or 5-hydroxy-(N,N)-dimethyltryptamine, crystallizes as a base in the monoclinic space group P2Ja with a= 17.95, b= 11.52, c= 14.24 ,~; fl= 131.29°; Z=8. Data were collected on a PAILRED automatic linear diffractometer. The structure was determined by the symbolic addition procedure and refined by the method of full-matrix least-squares to R= 0-054 for 1748 observed reflexions. The molecular structures of the two molecules in the asymmetric unit are almost identical. The indole nucleus of the A-molecule is planar; in the B-molecule there is a small angle of 1.5 ° between the pyrrole and benzene portions of the ring system. The ethylamine chain is almost fully extended, and lies approximately in a plane which is nearly perpendicular to the indole nucleus. This conformation is defined by the torsion angles r1, which is 87 and 72 ° for molecules A and B respectively, and r2 (175 and 170°).There are normal O-H.--N hydrogen bonds linking the A-molecules (2.68 A,) and the B-molecules(2.72 A) separately in two similarly arranged hydrogen-bonding systems.